Images Showing Before, During and After Blasting at ‘Lord Penrhyn’s Slate Quarries’ These three images show before, during and after the blasting at the quarry, it is noted that it involved the ‘removal of talcen mawr, 125,000 tons by means of 7 ½ tons of gunpowder’. It is noted to have been taken by 4 and 5 Stereoscopic Co., 54, Cheapside, E.C. 27 April 1895